Note 1 to entry: The complex number represented by the pair (a, b) can also be represented by a+jbMathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqk0di9Wr=fpeei0di9v8qiW7rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaeaaciWacmGadaGadeaabaGaaqaaaOqaaiaadggacqGHRaWkju gibiaacQgakiaadkgaaaa@3D03@ .

Note 2 to entry: The imaginary unit j and its opposite −j are the two square roots of −1.

Note 3 to entry: In electrotechnology, the symbol j is preferred to the symbol i, usual in mathematics and other fields.